The present invention relates generally to transfer grids for cooling while transferring hot ferrous and non-ferrous metal plates formed in a plate mill and the like. More particularly, the present invention relates to rollers mounted thereto to engage the plates being transferred so that friction between the plates and the grid is avoided or reduced.
My prior U.S. Pat. Nos. 5,265,711 and 5,301,785, which are hereby incorporated herein by reference, disclose the clamping of roller supporting inserts in transfer grid pockets for moving of the plates over the rollers. The roller is rotatably mounted by means of a bushing on an axle the ends of which are secured in apertures in plates. Members forward and aft of the roller and sandwiched between and welded to the plates form a frame in which the roller is mounted. See also my prior U.S. Pat. Nos. 5,908,102 and 5,921,370 which also dislcose inserts containing rollers for cooling bed plate transfer grids. My prior U.S. Pat. No. 5,908,102 also discloses that the insert is invertible to allow unworn portions of the bearings to experience axle contact whereby the bearing life is increased. See also my PCT application PCT/US97/24259.
It is also considered desirable to have the ability to install the inserts in a grid at a remote location (insert supplier""s business location) where suitably skilled workers are available to allow the cooling bed operator to make the changeover more quickly and inexpensively and without the need on site for people skilled in insert installation.
The inserts disclosed in my aforesaid patents have worked well. However, it is considered desirable to provide a less expensive structure for mounting rollers to the grid which is also easy to install and which allows the roller width to be increased to nearly the distance between longitudinal grid members for increased capacity.
The question was raised by a customer whether axles for the rollers could be rotatable in bearing blocks which are received in cutouts in the upper edges of grid members.
U.S. Pat. No. 2,593,089 discloses a conveyor having structural side members having upper edges and between which conveyor rollers are mounted. A bearing allows rotation of each roller on a shaft. The ends of the shaft are received in grooves in the upper edges of retaining strips, which are then slidably engaged in grooves thereby covering the grooves with the shaft ends therein. In an alternative embodiment, each end of the shaft has a bearing which is described, in a teaching away from the present invention, as xe2x80x9cpressed into hole 3a instead of a slot in retaining strip 4a.xe2x80x9d Such a structure does not allow easy installation.
My PCT application PCT/US99/00932 (International Publication no. WO 99/36277, published Jul. 22, 1999) discloses an axle mounting assembly for a vehicle wherein a U-shaped member or yoke defines a vertical upwardly opening slot for receiving an axle, and a block closes the opening to the slot. A wheel is rotatably mounted on the axle.
Other patents which may be of interest are U.S. Pat. Nos. 3,509,978 and 5,472,179.
A data sheet (no. 76.26-01.012, dated 1988) of Glacier GMBHxe2x80x94Deva Werke discloses the use of Deva metal plain bearings for rollers in a cooling bed for sheet steel in a French rolling mill. The pictures and drawing shown thereon appear to show the bearing between the roller and shaft and the shaft ends thus rigidly received in apertures in a respective pair of adjacent elongate members constituting the bed. Again, such a construction would not allow easy installation. In addition, bearings mounted between the roller and shaft wear out faster and are more subject to catastrophic damage when worn than if they were placed at the axle ends.
Accordingly, it is an object of the present invention to provide an inexpensive and easy to install yet reliable structure for securing in cutouts in the upper edges of parallel members of a cooling bed plate transfer grid a pair of bearings disposed in the cutouts for an axle for a roller to be received between the parallel members.
It is still another object of the present invention to be able to allow installation of the rollers in a grid at a remote location.
It is yet another object of the present invention to double or otherwise significantly increase bearing life for great savings to the customer.
It is another object of the present invention to be able to quickly and easily adjust the roller height, including returning the roller height to a desired height to compensate for the effects of wear over time.
In order to secure the bearings in the cutouts, in accordance with the present invention, a bearing is clamped in a cut-out by means of a plate which is received in a pair of slots in forward and aft edges of the cut-out to clampingly overlie the bearing.
Also in accordance with the present invention, means are provided for preventing movement laterally of each bearing, the lateral movement preventing means preferably comprising a lip on the respective bearing which is positioned and sized to abut a lateral surface of a respective grid member and a shoulder on the axle which engages the respective bearing.
In order to double or otherwise significantly increase bearing life for great savings to the customer, the bearing blocks are formed to be symmetrical from top to bottom so as to be invertible.
In order to quickly and easily adjust the roller height, the center of the bearing block aperture (which receives the axle) is offset from the center of the bearing block.
The above and other objects, features, and advantages of the present invention will be apparent in the following detailed description of the preferred embodiment thereof when rad in conjunction with the accompanying drawings wherein the same reference numerals denote the same or similar parts throughout the several views.